Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756557Ab1E0TXv (ORCPT ); Fri, 27 May 2011 15:23:51 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:46699 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755990Ab1E0TXq (ORCPT ); Fri, 27 May 2011 15:23:46 -0400 Subject: [PATCH 1/2] mm: Wait for writeback when grabbing pages to begin a write To: Christoph Hellwig , Alexander Viro , "Darrick J. Wong" From: "Darrick J. Wong" Cc: Jens Axboe , Theodore Tso , "Martin K. Petersen" , Jeff Layton , Dave Chinner , linux-kernel , Dave Hansen , linux-mm@kvack.org, Chris Mason , Joel Becker , linux-scsi , linux-fsdevel , Jan Kara , linux-ext4@vger.kernel.org, Mingming Cao Date: Fri, 27 May 2011 12:23:34 -0700 Message-ID: <20110527192334.32105.99904.stgit@elm3c44.beaverton.ibm.com> In-Reply-To: <20110527192326.32105.34164.stgit@elm3c44.beaverton.ibm.com> References: <20110527192326.32105.34164.stgit@elm3c44.beaverton.ibm.com> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1186 Lines: 39 When grabbing a page for a buffered IO write, the mm should wait for writeback on the page to complete so that the page does not become writable during the IO operation. This change is needed to provide page stability during writes for all filesystems. Signed-off-by: Darrick J. Wong --- mm/filemap.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index bcdc393..dac95a2 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2327,7 +2327,7 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, repeat: page = find_lock_page(mapping, index); if (page) - return page; + goto found; page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~gfp_notmask); if (!page) @@ -2340,6 +2340,8 @@ repeat: goto repeat; return NULL; } +found: + wait_on_page_writeback(page); return page; } EXPORT_SYMBOL(grab_cache_page_write_begin); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/